Is 3D MPRAGE better than the combination DIR/PSIR for cortical lesion detection at 3T MRI?
Flavia Nelson1, Aziz Poonawalla2, Sushmita Datta2
1Multiple Sclerosis Research Group, Department of Neurology, University of Texas Health Science Center at Houston, Houston, TX, USA.
Background And Objectives:
Based on the application of newer magnetic resonance imaging (MRI) acquisition sequences, the detection of cortical lesions (CL) in multiple sclerosis (MS) has significantly improved. Double inversion recovery (DIR) at 3T has increased the detection sensitivity and classification specificity when combined with phase sensitive inversion recovery (PSIR). Previous findings with 3D magnetization prepared rapid acquisition with gradient echo (MPRAGE) sequences, showed improved classification specificity of purely intracortical (IC) and mixed (MX) lesions, compared to the classification based on DIR/PSIR. Direct comparison between the detection of CL by 3D MPRAGE and by DIR/PSIR at 3T has not been evaluated.
Methods:
Eleven subjects were imaged on a 3T magnet. DIR/PSIR and 3D MPRAGE images were reviewed independently. Each image set was reviewed twice; only lesions detected on both sessions were scored. Review time per scan was ~5min for DIR/PSIR and ~15min for 3D MPRAGE.
Results:
We identified 141 CL (62 IC+79 MX) based on DIR/PSIR images vs. 93 (38 IC+55 MX) based on MPRAGE from all eleven patients. MPRAGE under-detected the number of CL in seven cases and over-detected the number of CL in three, only one case had the same number of CL on both sets of images.
Conclusions:
Combination DIR/PSIR at 3T is superior to 3D MPRAGE for detection of cortical gray matter lesions in MS. The contrast-to-noise ratio of CL appears to be inferior on the MPRAGE images relative to DIR/PSIR.
Insights
Double inversion recovery with phase sensitive inversion recovery (DIR/PSIR) at 3T detects more cortical lesions in multiple sclerosis (MS) than 3D MPRAGE. DIR/PSIR offers superior sensitivity for MS cortical lesion detection compared to 3D MPRAGE.
Area of Science:
- Neuroimaging
- Radiology
- Neurology
Background:
- Advanced magnetic resonance imaging (MRI) sequences improve cortical lesion (CL) detection in multiple sclerosis (MS).
- Double inversion recovery (DIR) combined with phase sensitive inversion recovery (PSIR) at 3T enhances sensitivity and specificity for CL detection.
- Previous studies suggested 3D magnetization prepared rapid acquisition with gradient echo (MPRAGE) improved classification specificity for intracortical (IC) and mixed (MX) lesions.
Purpose of the Study:
- To directly compare the detection capabilities of 3D MPRAGE and DIR/PSIR sequences at 3T for cortical lesions in MS.
- To evaluate the sensitivity and specificity of each sequence in identifying and classifying MS-related cortical lesions.
Main Methods:
- Eleven subjects with MS were scanned using both DIR/PSIR and 3D MPRAGE sequences on a 3T MRI scanner.
- Images from each sequence were independently reviewed twice, with only consistently detected lesions scored.
- The review time for DIR/PSIR was approximately 5 minutes, while for 3D MPRAGE it was approximately 15 minutes per scan.
Main Results:
- DIR/PSIR identified a total of 141 CL (62 IC, 79 MX), whereas 3D MPRAGE identified 93 CL (38 IC, 55 MX).
- 3D MPRAGE under-detected CL in seven patients and over-detected in three, with only one patient showing identical CL counts across both sequences.
- Cortical lesions appeared to have a lower contrast-to-noise ratio on MPRAGE images compared to DIR/PSIR.
Conclusions:
- The combination of DIR/PSIR at 3T is superior to 3D MPRAGE for detecting cortical gray matter lesions in MS.
- DIR/PSIR demonstrates higher sensitivity for detecting MS cortical lesions compared to 3D MPRAGE.
- The inferior contrast-to-noise ratio of CL on MPRAGE images contributes to its reduced detection performance.
